/*
 * Copyright 2020 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#ifndef SkSVGFilterContext_DEFINED
#define SkSVGFilterContext_DEFINED

#include "include/core/SkRect.h"
#include "include/core/SkRefCnt.h"
#include "include/core/SkString.h"
#include "modules/svg/include/SkSVGTypes.h"
#include "src/core/SkTHash.h"

class SkImageFilter;
class SkSVGFeInputType;
class SkSVGRenderContext;

class SkSVGFilterContext {
public:
    SkSVGFilterContext(const SkRect &filterEffectsRegion, const SkSVGObjectBoundingBoxUnits &primitiveUnits)
        : fFilterEffectsRegion(filterEffectsRegion),
          fPrimitiveUnits(primitiveUnits),
          fPreviousResult({ nullptr, filterEffectsRegion, SkSVGColorspace::kSRGB })
    {}

    const SkRect &filterEffectsRegion() const
    {
        return fFilterEffectsRegion;
    }

    const SkRect &filterPrimitiveSubregion(const SkSVGFeInputType &) const;

    const SkSVGObjectBoundingBoxUnits &primitiveUnits() const
    {
        return fPrimitiveUnits;
    }

    void registerResult(const SkSVGStringType &, const sk_sp<SkImageFilter> &, const SkRect &, SkSVGColorspace);

    void setPreviousResult(const sk_sp<SkImageFilter> &, const SkRect &, SkSVGColorspace);

    bool previousResultIsSourceGraphic() const;

    SkSVGColorspace resolveInputColorspace(const SkSVGRenderContext &, const SkSVGFeInputType &) const;

    sk_sp<SkImageFilter> resolveInput(const SkSVGRenderContext &, const SkSVGFeInputType &) const;

    sk_sp<SkImageFilter> resolveInput(const SkSVGRenderContext &, const SkSVGFeInputType &, SkSVGColorspace) const;

private:
    struct Result {
        sk_sp<SkImageFilter> fImageFilter;
        SkRect fFilterSubregion;
        SkSVGColorspace fColorspace;
    };

    const Result *findResultById(const SkSVGStringType &) const;

    std::tuple<sk_sp<SkImageFilter>, SkSVGColorspace> getInput(const SkSVGRenderContext &,
        const SkSVGFeInputType &) const;

    SkRect fFilterEffectsRegion;

    SkSVGObjectBoundingBoxUnits fPrimitiveUnits;

    skia_private::THashMap<SkSVGStringType, Result> fResults;

    Result fPreviousResult;
};

#endif // SkSVGFilterContext_DEFINED
